Reduced Fat Yogurt Chocolate Cake

I found this recipe in the "Joy of Cooking". I reduced in half the amount of butter originally called for in this recipe and replaced it with coconut oil. This delicious white cake is so easy to make. Some nuts or dried fruit can be added onto this cake.

Ingredients:
2 1/4 cups sifted cake flour (instructions below)
1 tsp baking powder
1/2 tsp baking soda
1/2 tsp salt
2 tbs butter (at room temperature)
3 tbs coconut oil
1 cup sugar
1 egg
Egg white from 2 eggs
1 cup nonfat yogurt (room temperature)
1 tsp vanilla
1/3 cup cocoa powder
1/4 cup sugar
1/4 cup water

Directions:
In a medium bowl, sift together cake flour, baking powder, baking soda, and salt.
In a Kitchen Aid® machine, beat butter, coconut oil, and sugar until lightened in color (about 5 minutes). In a medium bowl, whisk together egg, egg white, and vanilla and gradually beat in to the sugar mixture. Add the flour mixture in 3 steps, alternating with yogurt in the second step. Continue beating on the low speed, scraping the sides of the bowl with a rubber spatula as necessary.
In a small bowl, combine cocoa powder, 1/4 cup sugar, and 1/4 cup water and whisk together until smooth. Add to this mixture about 1 cup of the batter and mix well.
Pour the batter into the pan without smoothing the surface and pour the cocoa batter over the plain batter, without smoothing the surface. Bake the cake for 1 hour or until a toothpick inserted in the center comes out clean. Let cool in the pan for 10 minutes. Slice a thin knife blade around the cake to detach it from the pan.